How can I correctly create this JOIN association such that an attempt to load a

Child

object successfully JOINs the data from the parent?

Edit: these tables were created outside of an ActiveRecord migration (they are also accessed by other, pre-existing, non-Ruby applications) so I have no ability to change their schema. I can think of some fancy metaprogramming approaches, like responding to

method_missing

, that might let me lazy-load the missing attributes through a join... but I'm afraid I'll end up having to re-implement a bunch of ActiveRecord, like

delete

,

create

, etc. (which will lead to bugs). So I'm looking for some native/clean(ish) way to accomplish this.